1. Field of the Invention
The present invention relates to a golf club head.
2. Description of the Related Art
Generally, on the face of a golf club head, a plurality of straight grooves are formed parallel to each other in the toe-and-heel direction. These grooves are called score lines, marking lines, face lines, or the like (to be referred to as score lines in this specification). These score lines have an effect of increasing the backspin amount of a shot or suppressing a significant decrease in the backspin amount rate of a shot in case of a rainy day or a shot from the rough.
U.S. Pat. Nos. 3,869,126 and 5,029,864 each disclose a golf club head in which grooves having triangular cross sections are formed on the face as grooves similar to score lines. U.S. Pat. Nos. 5,618,239 and 5,709,616 each disclose a golf club head (patter head) in which grooves having triangular cross sections are formed on the face. U.S. Pat. Nos. 5,688,190 and 5,690,561 each disclose a golf club head in which a pad having a plurality of ribs is stuck to the face. Japanese Patent Laid-Open No. 09-253250 discloses a golf club head in which grooves smaller than score lines are formed on the face in addition to the score lines.
The increase in the backspin amount of a shot obtained by changing the design of score lines is limited. Like a golf club head disclosed in Japanese Patent Laid-Open No. 09-253250, forming grooves in addition to score lines is effective in increasing the backspin amount of a shot. However, when grooves are formed in addition to score lines, a ball may be damaged.